The advent of highly active antiretroviral therapy has resulted in a decline in the incidence of opportunistic infections and in prolonged survival. Obstacles towards virus erradication include the presence of an infected quiescent pool, drug resistance, toxicities, and lack of adherence. The goal of genetic therapies is the replacement of the HIV-1-infected cell reservoir with cells that have been genetically engineered to resist HIV-1 replication. The overall goal of the Gene and Cellular Therapy Core (Core G) is to provide scientific and technical support for clinical and laboratory projects that require the use of retroviral vector technology and hematopoietic stem cell (HSC) purification. The Specific Aims are: 1) To provide technical and logistical support for the implementation of human gene therapy trials in HIV. In a Good Manufacturing Practice facility, the Core provides the following services to investigators involved in clinical research in HIV/AIDS Gene Therapy: a) Large scale hematopoietic progenitor cell (HPC) manipulation and purification, b) Large-scale transduction of hematopoietic progenitors, c) Assessment of vector presence and expression in cells of various hematopoietic lineages, d) Performance of safety release assays in the final cellular product, e) Regulatory advice. 2) To provide technical and logistical support to basic science research in gene therapy, hematopoiesis and pathogenesis of HIV infection.The Core provide the following services to investigators involved in preclinical HIV Gene Therapy research: a) HPC banked by source, purity, gender, and donor HLA haplotype, for use in in vitro and for SCID-hu model experimentation, b) Stem cell assays, c) Banking of retroviral vector gene therapy reagents such as packaging cell lines, reporter genes and packaging plasmids. 3) To serve as an interface between clinical and basic science research groups by coordinating and the use of clinical specimens in basic science research. Samples include CD34+ cells transduced with various anti-HIV reagents and blood and bone marrow mononuclear cell samples from patients participating in gene therapy protocols.